System and method for secure biometric identification

ABSTRACT

A system and method for secure biometric identification. The inventive system includes a mobile unit and a server. The mobile unit is adapted to receive biometric input and provide a first signal in response thereto. In the illustrative implementation, the mobile unit is a Personal Digital Assistant (PDA) and the biometric input is provided by a fingerprint sensor mounted thereon. A first transceiver is mounted on the PDA for transmitting the first signal and receiving a second signal in response thereto. The PDA is adapted to encrypt the first signal and decrypt the second signal. A secure device is mounted at the PDA. The secure device has two modes of operation: a first locked mode by which access thereto is prohibited and a second unlocked mode by which access thereto is enabled on receipt of the second signal. In the illustrative implementation, the secure device is an encrypted database for which the second signal is a decryption key. The server unit includes a second transceiver for receiving the first signal transmitted via the wireless link. The first and second transceivers are adapted to operate in accordance with the Bluetooth specification. The server is equipped with a system for authenticating the biometric data and providing the second signal in response thereto. The second signal is then communicated to the mobile unit where it is utilized to access the secure device, e.g., encrypted database.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to electronic devices and systems. More specifically, the present invention relates to systems and methods for providing user identification and/or authentication for electronic devices and systems.

2. Description of the Related Art

Currently, whenever a user wishes to access a computer-based system containing private data, the user must often identify himself, usually with a password. Passwords notoriously provide poor security as users either chose very simple, easily ascertained passwords or, if they use more difficult passwords, users often write them down, making them subject to theft.

In the end, most forms of encryption, as well as access controls such as passwords and even locks, serve a single purpose of identifying the person requesting access.

Hence, there is a need in the art for a reliable, secure system or method of authenticating the identity of a user. Ideally, the system or method would be effective such that one would not need to memorize passwords or utilize other authenticating devices such as keys to access computers and other electronic devices and systems.

SUMMARY OF THE INVENTION

The need in the art is addressed by the system and method for secure biometric identification of the present invention. The inventive system includes a mobile unit and a server. In the illustrative embodiment, the mobile unit is adapted to receive biometric input and provide a first signal in response thereto. A first transceiver is included for transmitting the first signal and receiving a second signal in response thereto. In an illustrative embodiment, a secure device is operationally coupled to the mobile unit. The secure device has two modes of operation: a first locked mode by which access thereto is prohibited and a second unlocked mode by which access thereto is enabled on receipt of the second signal.

The server unit includes a second transceiver for receiving the first signal transmitted via the wireless link. The server is equipped with a system for authenticating the biometric data and providing the second signal in response thereto. The second signal is then communicated to the mobile unit where it is utilized to access the secure device.

In the illustrative embodiment, the first and second transceivers are adapted to operate in accordance with the Bluetooth specification. Preferably, the mobile unit is adapted to encrypt the first signal and decrypt the second signal. In the illustrative implementation, biometric input is provided by a fingerprint sensor mounted on a Personal Digital Assistant. The secure device in the illustrative implementation is an encrypted database for which the second signal is a decryption key.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a perspective front view of an illustrative implementation of a PDA adapted for use in accordance with the teachings of the present invention.

FIG. 1 b is a perspective rear view thereof.

FIG. 2 is a block diagram of an illustrative implementation of a mobile unit subsystem constructed in accordance with the present teachings.

FIG. 3 is a block diagram of an illustrative implementation of a server subsystem for use in the system for secure biometric identification of the present invention.

FIG. 4 is a flow diagram illustrative of a method for secure biometric identification implemented in accordance with the teachings of the present invention.

DESCRIPTION OF THE INVENTION

Illustrative embodiments and exemplary applications will now be described with reference to the accompanying drawings to disclose the advantageous teachings of the present invention.

While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, and embodiments within the scope thereof and additional fields in which the present invention would be of significant utility.

As mentioned above, and in accordance with the present teachings, the inventive system includes a mobile unit and a server. In the illustrative embodiment, the mobile unit is a Personal Digital Assistant (PDA) adapted to receive biometric input from a fingerprint sensor and provide a first signal in response thereto. Personal Digital Assistants are well known and widely used.

FIG. 1 a is a perspective front view of an illustrative implementation of a PDA adapted for use in accordance with the teachings of the present invention. FIG. 1 b is a perspective rear view thereof. In the preferred embodiment, the PDA is implemented in accordance with the teachings of copending U.S. utility patent application, filed on Mar. 21, 2000, entitled “SYSTEM AND METHOD FOR SECURE USER IDENTIFICATION WITH BLUETOOTH ENABLED TRANSCEIVER AND BIOMETRIC SENSOR IMPLEMENTED IN A HANDHELD COMPUTER”, inventor Martin Morris, (Atty. Docket No. WIDC-011), which teachings are hereby incorporated herein by reference. As disclosed in the reference application, in the best mode, the PDA 10 is equipped with an expansion slot 12 such as the Visor™, Handheld Computer manufactured and sold by Handspring and disclosed more fully at www.handspring.com. As shown in FIG. 1 b, the expansion slot 12 is adapted to receive a card 14 on which a biometric device, in the illustrative embodiment—a fingerprint sensor 16, is disposed. In addition, in accordance with the present teachings, a transceiver 22 is also disposed on the card 14. In the preferred embodiment, the transceiver 22 is adapted to operate in accordance with the BLUETOOTH SPECIFICATION VERSION 1.0A CORE, published in July 1999. When the card is inserted into the expansion slot, it interfaces electrically with the system bus of the PDA and provides an electrical circuit depicted in FIG. 2.

FIG. 2 is a block diagram of an illustrative implementation of a mobile unit subsystem constructed in accordance with the present teachings. The mobile unit subsystem 20 includes the wireless transceiver 22 which is adapted to communicate with a central processing unit (CPU) 26 of the PDA. The central processing unit 26 receives biometric data from the fingerprint sensor 28. In accordance with the present teachings, data from the fingerprint sensor 28 is encrypted in either in software 30 adapted to run on the CPU 26 and/or in optional hardware 32. Encryption hardware and software are well known in the art. The control software 30 also enables the CPU 26 to selectively access and control the mobile unit components via a system bus shown generally at 38.

The encrypted biometric data is either used locally to access an encrypted database 34 or, preferably, transmitted over a link such as a wireless link to a server subsystem via the transceiver 22 and antenna 24. The server subsystem is depicted in FIG. 3.

FIG. 3 is a block diagram of an illustrative implementation of a server subsystem for use in the system for secure biometric identification of the present invention. The encrypted biometric data signal is received by a server antenna 42 and a second wireless Bluetooth enabled transceiver 44. The received signal is decrypted by an optional conventional hardware based decryption circuit 46 and/or by decryption software implemented in control software 48 adapted to run on a server CPU 50. Those skilled in the art will appreciate that the decryption scheme utilized on the server is designed to match that of the mobile unit 20. In the preferred embodiment, the RSA public key encryption scheme is used. This scheme is disclosed more fully in U.S. Pat. No. 4,405,829 entitled Cryptograpgic Communications System & Method, issued Sep. 29, 1983 to Rivest, et al. the teachings of which are incorporated herein by reference. The server control software also controls the CPU 50 to selectively access and control the components of the server subsystem 40 via a server subsystem bus shown generally at 51.

In accordance with the present teachings, the decrypted biometric data, in the illustrative implementation, the decrypted fingerprint, is compared by fingerprint matching software 52 to a database 54 of biometric data, i.e., fingerprints. Fingerprint matching software is well known in the art. Such software may be purchased from Veridicom, Inc. of Santa Clara, Calif.

When a match is achieved, a user is identified and an authentication key specific to the identified mobile user is retrieved from an encryption key database by the CPU 50 via the bus 51. In the preferred embodiment, the retrieved encryption key is encrypted by the resident encryption scheme either by the hardware unit 46, if provided, and/or by the encryption software implemented in the control software 48. The encrypted encryption key is then transmitted back to the mobile unit 20 via the wireless link through the transceiver 44 and antenna 42. As an alternative, the encrypted encryption key may be provided to a network 59 via a first network interface. card or circuit 58 and a second network interface card or circuit 66. The network 59 facilitates the communication of the encrypted encryption key to the mobile unit 20 via a wireless transceiver 62 and an antenna 64. This configuration may be preferred if the second antenna 64 is closer to the mobile unit 20.

In addition, those skilled in the art will appreciate that the inventive system can be implemented such that the encrypted biometric data is transmitted from a first PDA 20 and the encrypted encryption key or other information is sent to a second mobile unit or over a network to a second server or network of devices.

Returning to FIG. 2, on receipt of the encrypted encryption key from the server subsystem 40 via the antenna 24 and the wireless transceiver 22, the mobile unit CPU 26 decrypts the encrypted key using the resident software and/or hardware decryption facility 30 and 32, respectively. The decrypted encryption key is then used by the CPU 26 to access a secure device. In an illustrative embodiment, the secure device is an encrypted database 34 mounted on the mobile unit. Those skilled in the art will appreciate that the secure device need not be mounted on the mobile unit 20. As an alternative, the secure device may be coupled to the mobile unit via the wireless link.

In any event, the secure device, i.e., database 34, has two modes of operation: a first locked mode by which access thereto is prohibited and a second unlocked mode by which access thereto is enabled on receipt of the decrypted encryption key. For optimal security, the decryption key for the encrypted database 34 should not be stored on the mobile unit. On receipt of the decrypted decryption key, a working copy 36 of the encrypted database 34 is created.

FIG. 4 is a flow diagram illustrative of a method for secure biometric identification implemented in accordance with the teachings of the present invention. As shown in FIGS. 2, 3 and 4 when a user in possession of the mobile unit 20 wishes to access the secure device 34, he/she places a finger on the fingerprint sensor 28 and starts the access control program 100.

At step 104, the CPU 26 running the access control software 30 scans the fingerprint from sensor 28 and, at step 106, encrypts it with the public key of the authentication server 40 by using the encryption software or hardware 30, 32.

At step 108, the resulting encrypted message is sent to the server 40 via the transceiver 22 and antenna 24 on the mobile unit 20 and the antenna 42 and transceiver 44 of the server 40. As mentioned above, as an alternative, the encrypted fingerprint is sent via the access point 60 and local or wide-area network 59 when the server 40 is not within direct radio range of the mobile unit 20.

At step 110, when the authentication request is received at the server 40, the server CPU 50 decrypts the message using its secret key and the encryption hardware and/or software 46 and 48, respectively.

At step 112, the CPU 50 then utilizes the fingerprint match software 52 to compare the decrypted fingerprint to the database of authorized fingerprints 54 to determine if the request is valid.

If the request is valid, then, at step 114, the decryption key for the user's encrypted database 34 (FIG. 2) is retrieved from the key database 56 (FIG. 3).

At step 116, the key is encrypted via the encryption hardware or software 46, 48 (FIG. 3) and, at step 118, sent back to the mobile unit 20 via the same path from which the request was originally received.

At the mobile unit 20, at steps 122 and 124, the key is received and decrypted.

At step 126, the retrieved key used to make a temporary working copy 36 of the encrypted database 34.

At step 128 this temporary copy 36 is either read or edited. If edited, then at step 130 the edited working copy is deleted or rewritten to encrypted form as soon as the user completes his operation.

Thus, the present invention has been described herein with reference to a particular embodiment for a particular application. Those having ordinary skill in the art and access to the present teachings will recognize additional modifications applications and embodiments within the scope thereof.

It is therefore intended by the appended claims to cover any and all such applications, modifications and embodiments within the scope of the present invention.

Accordingly, 

1-59. (canceled)
 60. A mobile wireless communications device, comprising: a biometric sensor that is part of a card that is received by the mobile wireless communications device a processor operatively coupled to the biometric sensor; and an encrypted database operatively coupled to the processor, wherein the mobile wireless communications device wirelessly transmits biometric information, wherein the mobile wireless communications device wirelessly receives a cryptographic key in response to the transmitted biometric information, and wherein the cryptographic key is used to decrypt at least a portion of the encrypted database.
 61. The mobile wireless communications device according to claim 60, wherein the biometric sensor comprises a fingerprint sensor.
 62. The mobile wireless communications device according to claim 61, comprising: control software running on the processor.
 63. The mobile wireless communications device according to claim 60, wherein the processor comprises a central processing unit.
 64. The mobile wireless communications device according to claim 62, comprising: a wireless transceiver operatively coupled to the processor.
 65. The mobile wireless communications device according to claim 64, comprising: encryption circuitry operatively coupled to the processor.
 66. The mobile wireless communications device according to claim 65, comprising: a working database operatively coupled to the processor.
 67. The mobile wireless communications device according to claim 65, wherein the biometric information is derived from information generated by the biometric sensor.
 68. The mobile wireless communications device according to claim 67, wherein the mobile wireless communications device is part of a personal digital assistant (PDA).
 69. The mobile wireless communications device according to claim 67, wherein the wireless transceiver comprises a Bluetooth-enabled wireless transceiver.
 70. A system for secure identification, comprising: a first handheld wireless communications device comprising a biometric sensor, a first processor, a secure device and a first wireless transceiver, the biometric sensor being part of a card, the card being received by the handheld wireless communications device, the first processor being in communication with the biometric sensor and the first wireless transceiver; the secure device storing an encrypted database, and a second communications device in communication with the first handheld wireless communications device, the second communications device comprising a second processor, a second transceiver and software, the second processor being operatively coupled to the second transceiver, the software authenticating a signal transmitted by the first wireless transceiver and received by the second transceiver and providing a cryptographic key in response to the authenticated signal, wherein the cryptographic key is used by the first handheld wireless communications device to decrypt at least a portion of the encrypted database.
 71. The system according to claim 70, wherein the cryptographic key comprises a public key.
 72. The system according to claim 70, wherein the first handheld wireless communications device comprises a personal digital assistant (PDA).
 73. The system according to claim 70, wherein the first wireless transceiver comprises a Bluetooth-enabled wireless transceiver.
 74. The system according to claim 73, wherein the second transceiver comprises a second Bluetooth-enabled wireless transceiver.
 75. The system according to claim 73, wherein the second wireless communications device comprises an access point.
 76. The system according to claim 70, wherein the first handheld wireless communications device and the second communications device communicate via a local area network.
 77. The system according to claim 70, wherein the first handheld wireless communications device and the second communications device communicate via a wide area network.
 78. The system according to claim 70, wherein the first handheld wireless communications device and the second communications device communicate via an access point.
 79. The system according to claim 70, wherein the first handheld wireless communications device comprises a mobile wireless communications device. 